William Kelly · Matthew 17

But at the foot of that same mountain where the Lord displayed the glory of the kingdom, Satan also displayed his power. It was not broken yet. The kingdom was only a matter of testimony. The disciples failed to draw on the resources of Christ to put down the power of the enemy. A man comes to the Lord, kneeling down to Him and saying, "Lord, have mercy on my son; for he is lunatic and sore vexed; for ofttimes he falleth into the fire, and oft into the water" — the most opposite trials were thus brought together. "And I brought him to Thy disciples, and they could not cure him. Then Jesus answered and said, O faithless and perverse generation, how long shall I be with you? how long shall I suffer you? Bring him hither to Me. And Jesus rebuked the devil, and he departed out of him. And the child was cured from that very hour" (vers. 15-18). The disciples wanted to know how it was that they could not cast him out, and He tells them, "Because of your unbelief." It is as sad as wonderful that unbelief is at the root of the difficulties Satan foists in; for he has lost his power over those that have faith. This child is a lunatic and sore vexed; but unbelief is unable to use the power of God, which ought to have been at the command of the disciples. "If ye have faith as a grain of mustard-seed, ye shall say unto this mountain, Remove hence to yonder place." The least working of faith in the soul is so far available for present difficulties. The power of the world, the settled power of anything here, which is what the mountain sets forth, would completely disappear before faith. "Howbeit this kind goeth not out but by prayer and fasting" (vers. 20, 21). There must be dependence upon God in the conflict with the power of evil. It was Christ's moral glory and the secret of strength. The assumption of power, because of association with Jesus, simply fails and turns to shame. There must also be self-emptiness and self-denial, that God may act. When Jesus descends all Satan's power is broken and vanishes.